Concern on conservation of tropical forests and the necessity to recover degraded areas, has caused increasing on the demand for forest species seedlings and consequently seeds. To obtain good quality seedlings are necessary good origin seeds, and it is important those seeds have been stored properly to maintain their quality. Therefore, the species have different requirements, which makes necessary studies of storage methods. Those seeds with desiccation tolerance, called orthodox seeds, have higher longevity when compared to recalcitrant ones, with low tolerance to desiccation and reduced longevity, requiring different storage conditions. Handroanthus heptaphyllus (Vell.) Mattos, ipe-roxo, is a species of Family Bignoniaceae which has many uses; its excellent wood quality is used for construction of floors; its flowers of great beauty made it widely used in landscaping; it is ecvologically important restouration programs. Species of genus Handroanthus have large amount of winged seeds being dispersed by wind. Their seeds have orthodox behavior for storage, but when they not stored properly lose quickly their viability. Seeking for the development of new techniques which prolong the viability of seeds of forest tree species, the objective of the study was to store Handroanthus heptaphyllus (Vell.)seeds through two ways: Study 1 - to store germinated seeds into the substrate with different levels of water retention capacity; Study 2 - to prolong the storage time of germinated seeds restoring the desiccation tolerance of primary root by polyethyleneglycol (PEG) treatment. The storage was performed in cold chamber (10oC) in substrate with three levels of water retention capacity (0, 30 and 60%). Germinated seeds were evaluated monthly by nine months, under conditions of germination chamber at 25°C with light (8h/daily by30 days), and after set up to the nursery to monitor their development (greenhouse - 30 days; the shade house - 30 days; outdoor condition - 45 days). It was possible to store germinated seeds of ipe-roxo, as well as to restore desiccation of their tolerance. The results of Study 1 showed that is possible to store germinated seeds on 0% of water retention capacity for 7 months with around 50% of survival. In Study 2, the germinated seeds treated with PEG did not show prolonged storage period due to the high mortality occurred through the months. In both studies, the survival and the development of normal seedlings decreased by the time. Based on the results, we conclude that ipê-roxo can be storage as germinated seeds into the 0% water retention capacity, although, more studies are needed to develop this proposed methodology.
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